William stanley



(NoMode l.)

' W. STANLEY, Jr.

- AIR PUMP. I N0. 294.412. "Patented Mar. 4.. 1884 ATTESTS. INVENTUR.

train STATES lbrrnnr anion...

WILLIAM STANLEY, JR, O F ENGLEWOOD, NEW JERSEY.

' AIR-PUMP.

SPECIFICATION; formingpart of Letters Patent No. 294,412, dated March 4 1884,

Application filed April 27, 1862. (Xomodchl' To ctZ Z whom it may concern; 7

Belt known that I, WILLIAM STANLEY, J r.',

of Englewood, in the county of Bergen and- State of N ew Jersey, have invented a new and 5 useful Improvement in Air-Pumps, of which 7 the following is a specification.

In the manufacture of electric lamps it is of great importance to produce a substantially perfect vacuum inthe globes of such lamps, in order that the carbon or other incandescent material employed to retard the current of electricity and produce the light may be unaffected by the oxygen or other ingredients of the air, thepresence of whichwould cause combustion and the rapid destruction of the incandescent material, as well as the liability of electrolysis between its poles. Many forms of apparatus have been devised, and many in genious methods suggested and tried; but thus far such methods .and apparatus have been lacking in the requisite economy, by reason of the large amount of time required in the operation.

The present invention relates to an improved apparatus or air-pump especially designed'for exhausting the globes of electric lamps, but practical for forming vacuums in many other vessels; and it consists of a mercurial air-pump Working, substantially, upon the principle 'of the Sprengel pump, in combination with a common exhaust-pump worked by any clesired power, the two being so connected with the globe or other vessel to be exhausted that they co-operate to remove the air therefrom during the entire operation.

The invention isiIlustrated in the acco'mpanying drawing, which is a view in perspec tive of the apparatus with a globe in position to be exhausted, 'and in which erepresents a bulb or enlargement connected by a vertical tube, 1), to a second, 0, preferably larger than the bulb a. The bulb cis connected by a vertical tube, d, to a reservoir, 6, and by a tube, f, to an exhaust-pump, A. The upper bulb, a, is connected by a tube, 9, provided with a stop-cock, h, to a mercury-supply reservoir, 2, preferably funnel-shaped. The bulb a is also provided with a branch tube, j, tothe upper end of which the globe or other vessel to be 50 exhausted is attached by a short tube-or other means, by. which an air-tight connection is formed. The tube 9 preferably projects into the bulb a,so that its end is slightly above the line of the branch tube j, if extended to near the center of the bulb, and the lower half of 5 5 special importance is due to an enlargement of the tubes 1) and (1, whereby a chamber is formed, in which the air as it is forced from the tube 12 collects; and it should be of sufficient capacity to permit the columns or bubbles of air to become disengaged from the nier- 7o cury'as it falls through this bulb or chamber in its passage from the tube 1) to the tube d. The height of the tube (1 should beabout thirty or more inches, in order to prevent the mercury from rising into the bulb 0 when a vacuum is formed therein. The height of the tube 1),

or the vertical distance between the bulbs c and a, willdepend largely upon the degree of exhaust produced and maintained by the pump A. This distance should, however, in all cases be sufficient to prevent the air in the bulb 0, when under the exhaust of the pump, from passing upward through the descending mercury through the tube 5. If the force of the exhaust in the bulb c is represented by twentyeight inches, a vertical distance of ten or twelve inches between the bulbs will be sufficient for all practical purposes. The bore of the tube 22 should be quite small, so that the successive drops 'ofmercury will completely fill it, to pre- 9 vent the escape of the air upwardly.

The operation of the apparatus is, briefly, as follows: The parts being in position substantially as shown in the drawing, the reservoir t is supplied with mercury, the stop-cock h being closed, and, the lower end of the tube at being immersed in the cistern of mercury 6, by a few strokes of the-exhaust-pump A, the larger part of the air contained in the globe and in the tubes and bulbs connected there- IoO with is exhausted through the tubef. The stop-coclc h is then opened sut'ticiently to allow the mercury to descend through the tube r into the bulb a in a rapid succession of drops approaching a continuous stream, and thence through the tube b, bulb or chamber 0, and tube (1, where it displaces a portion of the mercury in said tube, causing it to flow into the reservoir 0. As the successive drops of mercury descend the tube 1), the air within such tube is forced downward, and an increased or more perfect vacuum is formed within the tube, into which the air contained in the globe 7t and bulb (L is constantly drawn, being caught at the mouth of the tube b'by the successive drops of mercury, and in turn carried down the tube into the bulb c. lvIGdIlWllllC the pump A is in continual operation, to exhaust the air from the bulb c as fast as it is delivered from the tube b. the ingress of air through the tube (1 being cftectually prevented by the column of mercury therein. During the operation, as

above described, short columns of air im- 2 pri'soned between columns of mercury are ob served to pass in rapid succession down the tube 1) and into the bulb c. TllQSO2Li1-COll11il1iS,

during the first stages of the operation, are of frequent occurrence and of considerable size; but as the operation advances they diminish both in frequency and size till only an occasional small bubble of air is seen to descend with the mercury.

Several globes or other vessels can be tached to the tube y or to its continuation, and exhausted at the same time by this apparatus, and the supply of mercury can be kept up by emptying the contents of the reservoir 0 into the reservoir I have, however, invented an apparatus by which several globes attached to separate tubes can be exhausted by means of a single exhaust-pump, and the mercury as it descends the tubes be raised to the desired height by the exhaust ot'the pump. This invention forms the subject of a separate application iiled contemporaneouslyherewith.

W'hat is claimed as new is- 1. The combination, in an apparatus for exhausting globes for electric lamps and other vessels, of a mercurial air-pump with a common exhaust-pump arranged to operate simul- V \VILLTAM STAXLEY, JR.

\Vitnesses:

Ji-urizs S. GREYES, R, F. GAYLonD. 

